Methods and Results

In seven goats, one disc was injected with chondroitinase ABC (mild degeneration) and after three months compared to control. Ex vivo, 50 caprine discs received physiological loading (50–150N) or overloading (50–400N) in a loaded disc culture system. To determine whether ECM degeneration is due to cell activity, half of the discs was subjected to freeze-thaw cycles. Spectroscopic images were collected at 1000–1300 cm⁻¹ and analyzed using multivariate curve resolution analysis.

In vivo, less proteoglycan was found in the degenerated group (p<0.05), especially in the nucleus. Collagen content was increased in the nucleus and anterior annulus, and had higher entropy (p<0.01), indicating matrix disorganization. In the ex vivo experiment, the proteoglycan/collagen ratio was decreased (p<0.05) in the vital group and there was an increase in collagen entropy (p<0.05). A significant interaction between loading and vitality was found in the amount of collagen (p<0.05), but not in the entropy.